/***********************************************************************
 * BinTrotter : BitTorrent library/client for the Android operating system.
 *  
 * Copyright (C) 2009, Christopher David Stones (chris.stones@gmail.com)
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 ***********************************************************************/

package org.bintrotter.apeer.sendstates;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.SocketChannel;

import org.bintrotter.apeer.Peer;

public class KeepAlive implements SendState {

	private Peer m_peer;
	private SocketChannel sc;
	private ByteBuffer bb;
	
	public KeepAlive(Peer peer) {
		
		m_peer = peer;
		sc = null;
		bb = null;
	}
	
	@Override
	public void reset() {

		sc = m_peer.channel();
		if(bb == null)
			bb = ByteBuffer.allocate(4);
		bb.rewind();
		bb.putInt(0);
		bb.rewind();
	}

	@Override
	public States update() {
		
		try {
			
			sc.write(bb);
			if(bb.hasRemaining() == false)
				return States.IDLE;
			
		} catch (IOException e) {
			
			return States.SHUTDOWN;
		}
		
		return States.KEEP_ALIVE;
	}

}
